1. Field of the Invention
The present invention relates in general to primary electrochemical cells, and more particularly, to zinc alkaline--manganese dioxide cells having zinc anodes in the form of a wrapped and/or layered, expanded metal mesh attached to a zinc casing.
2. Background Art
It is well known that zinc alkaline--manganese dioxide cells perform better than chloride electrolyte based Leclanche cells and heavy duty zinc chloride cells, especially at continuous heavy duty drains. Alkaline batteries generally have two performance advantages over non-alkaline batteries. In particular, alkaline batteries exhibit greater energy densities and higher discharge rates compared to non-alkaline cells. Such preferable characteristics are achieved by increasing the amount and efficiency of active material as well as by reducing voltage loss. The three primary factors through which these improvements are realized include: 1) modifying cathode construction and configurations to increase the surface area of the electrode and current collectors, 2) using a highly conductive alkaline electrolyte to improve electrical conductivity of the electrolyte, and 3) using a powdered zinc anode instead of a zinc casing to further increase the surface area of the anode.